The homolog of Ciboulot in the termite (Hodotermopsis sjostedti): a multimeric β-thymosin involved in soldier-specific morphogenesis

Abstract Background Caste differentiation in social insects is a type of polyphenism that enables division of labor among members of a colony. This elaborate social integration has attracted broad interest, although little is known about its regulatory mechanisms, especially in Isoptera (termites). In this study, we analyzed soldier differentiation in the damp-wood termite Hodotermopsis sjostedti, focusing on a possible effector gene for caste development. The gene for an actin-binding protein, HsjCib, which shows a high level of expression in developing mandibles during soldier differentiation, is characterized in detail. Results To examine the HsjCib gene, full-length cDNAs were obtained by rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR) and sequencing. Multiple isoforms were identified, and on the basis of the results of northern and Southern hybridization analyses, these isoforms were considered to be transcriptional variants from a single gene. On the basis of their sequence similarity to homologous genes of other organisms, functions in actin assembly were assumed to be different among isoforms. Expression analysis revealed high expression in the head during soldier differentiation, which was consistent with their allometric growth. Although isoform expression was observed in various tissues, different expression levels were observed among tissues, suggesting the possibility of tissue-specific morphogenetic regulation by HsjCib isoforms. Conclusion This study revealed the characteristics and dynamics of the HsjCib gene during soldier differentiation as a potential representative of downstream effector genes in caste-specific morphogenesis. From the expression patterns observed, this gene is considered to be involved in cephalic morphogenesis and neural reorganization, resulting in the establishment of caste-specific morphology and behavior.</p

Improving Compound–Protein Interaction Prediction by Self-Training with Augmenting Negative Samples

Identifying compound-protein interactions (CPIs) is crucial for drug discovery. Since experimentally validating CPIs is often time-consuming and costly, computational approaches are expected to facilitate the process. Rapid growths of available CPI databases have accelerated the development of many machine-learning methods for CPI predictions. However, their performance, particularly their generalizability against external data, often suffers from a data imbalance attributed to the lack of experimentally validated inactive (negative) samples. In this study, we developed a self-training method for augmenting both credible and informative negative samples to improve the performance of models impaired by data imbalances. The constructed model demonstrated higher performance than those constructed with other conventional methods for solving data imbalances, and the improvement was prominent for external datasets. Moreover, examination of the prediction score thresholds for pseudo-labeling during self-training revealed that augmenting the samples with ambiguous prediction scores is beneficial for constructing a model with high generalizability. The present study provides guidelines for improving CPI predictions on real-world data, thus facilitating drug discovery

Development of High Performance DC Fuse for Electric Vehicle and Its Features

Abstrac

Stabilization of SF₅⁻ with Glyme-Coordinated Alkali Metal Cations

The stabilization of complex fluoroanions derived from weakly acidic parent fluorides is a significant and ongoing challenge. The [SF₅]⁻ anion is recognized as one such case, and only a limited number of [SF₅]⁻ salts are known to be stable at room temperature. In the present study, glyme-coordinated alkali metal cations (K⁺, Rb⁺, and Cs⁺) are employed to stabilize [SF₅]⁻, which provides a simple synthetic route to a [SF₅]⁻ salt. The reactivities of KF and RbF with SF₄ are significantly enhanced by complexation with G4, based on Raman spectroscopic analyses. A new room-temperature stable salt, [Cs(G4)₂][SF₅] (G4 = tetraglyme), was synthesized by stoichiometric reaction of CsF, G4, and SF₄. The vibrational frequencies of [SF₅]⁻ were assigned based on quantum chemical calculations, and the shift of the G4 breathing mode accompanying coordination to metal cations was confirmed by Raman spectroscopy. Single-crystal X-ray diffraction revealed that Cs⁺ is completely isolated from [SF₅]⁻ by two G4 ligands and [SF₅]⁻ is disordered along the crystallographic two-fold axis. Hirshfeld surface analysis reveals that the H···H interaction between two neighboring [Cs(G4)₂]⁺ moieties is more dominant on the Hirshfeld surface than the interaction between the H atom in glyme molecules and the F atom in [SF₅]⁻, providing a CsCl-type structural model where the large and spherical [Cs(G4)₂]⁺ cations contact each other and the [SF₅]⁻ anions occupy interstitial spaces in the crystal lattice. The [SF₅]⁻ anion, combined with [Cs(G4)₂]⁺, exhibits a very limited deoxofluorinating ability toward hydroxyl groups in both neat conditions and THF solutions

Exploring ligand binding pathways on proteins using hypersound-accelerated molecular dynamics

生体分子の動きを効率的に捉えるシミュレーション技術を開発 --超高周波超音波照射によってタンパク質と医薬品の結合計算を加速--. 京都大学プレスリリース. 2021-05-28.Capturing the dynamic processes of biomolecular systems in atomistic detail remains difficult despite recent experimental advances. Although molecular dynamics (MD) techniques enable atomic-level observations, simulations of “slow” biomolecular processes (with timescales longer than submilliseconds) are challenging because of current computer speed limitations. Therefore, we developed a method to accelerate MD simulations by high-frequency ultrasound perturbation. The binding events between the protein CDK2 and its small-molecule inhibitors were nearly undetectable in 100-ns conventional MD, but the method successfully accelerated their slow binding rates by up to 10–20 times. Hypersound-accelerated MD simulations revealed a variety of microscopic kinetic features of the inhibitors on the protein surface, such as the existence of different binding pathways to the active site. Moreover, the simulations allowed the estimation of the corresponding kinetic parameters and exploring other druggable pockets. This method can thus provide deeper insight into the microscopic interactions controlling biomolecular processes

Comparison of carbon dioxide and air insufflation use by non-expert endoscopists during endoscopic retrograde cholangiopancreatography

Background: Endoscopic retrograde cholangiopancreatography (ERCP) is subject to several complications that include a lengthy procedure time, technical difficulty, and active bowel movement induced by air insufflation. In ERCP carried out by non-expert endoscopists who are prone to excessive luminal insufflation, insufflation with carbon dioxide (CO2) may provide better and safer outcomes. We aimed to assess the efficacy and safety of CO2 insufflation during ERCP by non-expert endoscopists. Methods: This study included 208 consecutive patients who received ERCP, excluding those in poor general health or with obstructive lung disease. The first operator for each patient was a non-expert endoscopist having done 50 or fewer ERCP procedures. Primary outcomes were the changes in cardiopulmonary state during ERCP. Secondary outcomes were ERCP complications. We designed a single-center, randomized, prospective, double-blind, controlled trial with CO2 and air insufflation during ERCP. Results: CO2 insufflation did not affect overall procedure progression or results. A positive correlation was observed between procedure time and change in maximal systolic blood pressure from baseline among patients in the air insufflation group, but not in the CO2 insufflation group (correlation coefficient 0.408 vs 0.114, change in the maximal systolic blood pressure from baseline +4.2 vs+1.2mmHg/10min). This was consistent with our findings in patients treated by the first operator alone. The occurrence rate of post-ERCP pancreatitis tended to be lower in the CO2 group than the air group (4/102 [3.9%]vs 0/106 [0%], P=0.056). Conclusions: CO2 insufflation during ERCP by non-expert endoscopists is recommended from the standpoints of efficacy and safety.ArticleDIGESTIVE ENDOSCOPY. 25(2):189-196 (2013)journal articl

Risk factors for pancreatic stone formation in autoimmune pancreatitis over a long-term course

Autoimmune pancreatitis (AIP) has the potential to progress to a chronic state that forms pancreatic stones. The aim of this study was to clarify the risk factors underlying pancreatic stone formation in AIP. Sixty-nine patients with AIP who had been followed for at least 3 years were enrolled for evaluation of clinical and laboratory factors as well as computed tomography and endoscopic retrograde cholangiopancreatography findings. During the course of this study, increased or de novo stone formation was seen in 28 patients, who were defined as the stone-forming group. No stones were observed in 32 patients, who were defined as the non-stone-forming group. Nine patients who had stones at diagnosis but showed no change during the course of this study were excluded from our cohort. Univariate analysis revealed no significant differences in clinical or laboratory factors associated with AIP-specific inflammation between the two groups. However, pancreatic head swelling (P = 0.006) and narrowing of both Wirsung's and Santorini's ducts in the pancreatic head region (P = 0.010) were significantly more frequent in the stone-forming group. Furthermore, multivariate analysis identified Wirsung and Santorini duct narrowing at diagnosis as a significant independent risk factor for pancreatic stone formation (OR 4.4, P = 0.019). A primary risk factor for pancreatic stone formation in AIP was narrowing of both Wirsung's and Santorini's ducts, which most presumably led to pancreatic juice stasis and stone development.ArticleJOURNAL OF GASTROENTEROLOGY. 47(5):553-560 (2012)journal articl

System Interface for an Integrated Intelligent Safety System (ISS) for Vehicle Applications

This paper deals with the interface-relevant activity of a vehicle integrated intelligent safety system (ISS) that includes an airbag deployment decision system (ADDS) and a tire pressure monitoring system (TPMS). A program is developed in LabWindows/CVI, using C for prototype implementation. The prototype is primarily concerned with the interconnection between hardware objects such as a load cell, web camera, accelerometer, TPM tire module and receiver module, DAQ card, CPU card and a touch screen. Several safety subsystems, including image processing, weight sensing and crash detection systems, are integrated, and their outputs are combined to yield intelligent decisions regarding airbag deployment. The integrated safety system also monitors tire pressure and temperature. Testing and experimentation with this ISS suggests that the system is unique, robust, intelligent, and appropriate for in-vehicle applications